Vehicles powered either fully or partially by batteries must at some point recharge their batteries. Particularly in the case of battery electric vehicles, the lack of an alternative power source, like one that a plug-in hybrid electric vehicle would have, causes the batteries to deplete faster and have a more limited range. Plug-in electric hybrids are generally less taxing on the batteries and built-in regenerative systems may suffice to recharge the batteries enough to go longer without having to plug-in the vehicle to recharge it. However, the driver will dictate the need for recharging an electric vehicle through the extent of use, driving conditions, and driving style. High mileage, stop-and-go traffic, and quick accelerations are all things that the driver may subject an electric vehicle to, and all will deplete the batteries faster than under ideal conditions.
The standard American electrical socket provides 120 volts A/C (alternating current). The common availability of the 120 volt A/C electricity supply makes it a convenient choice for the power supply for recharging the batteries of electric vehicles. Many garages, carports, or outdoor parking areas may currently have 120 volt A/C electrical outlets, or may easily have one added, so that the power source may be connected to the electric vehicle for Level I charging.
However, the 120 volt A/C electricity supply is often insufficient to recharge the batteries of an electric vehicle in a period of time to allow for convenient use of the electric vehicle. A full recharge may not even be completed overnight and partial recharges often take too much time to be practical. Providing a higher voltage electricity supply can greatly reduce the amount of time needed to recharge an electric vehicle. Such high voltage sources are available in homes and other locations, and may be used for Level II charging.
It is desirable to provide a convenient way of connecting the Level I or Level II electricity source to an electric vehicle to recharge the batteries thereby making recharging quicker and using an electric vehicle more practical. It is also desirable to provide a convenient way to plug the electric vehicle supply equipment to either a Level I or Level II electrical supply source using plugs and receptacles designed to meet National Electrical Manufacturers Association (NEMA) standards, and with minimal duplication of components. This will reduce the cost of the product, installation, service repair, relocation and greatly simplifying the local electrical permitting process. This will also make the electric vehicle more practical, acceptable and provide a lower cost of ownership for the vehicle consumer.